Dynamic magnetic resonance imaging and spectroscopie of experimental brain injury

1996 ◽  
Vol 8 (4) ◽  
pp. 76-86 ◽  
Author(s):  
K. Nicolay ◽  
R.M. Dijkhuizen ◽  
A. van der Toorn ◽  
T. Reese ◽  
D. Brandsma ◽  
...  
Keyword(s):  
Brain Injury ◽  
Magnetic Resonance ◽  
Animal Studies ◽  
Brain Research ◽  
Focal Cerebral Ischemia ◽  
Repeated Measurements ◽  
Laboratory Animals ◽  
Non Invasive ◽  
The Impact

SummaryThis article describes the use of non-invasive magnetic resonance (MR) methods for the characterization and monitoring of the pathophysiology of experimental brain injury in laboratory animals as a function of time and treatment. The impact of MR in brain research is primarily due to its non-invasive nature, thereby enabling repeated measurements in long-term studies, and due to the type of information that it provides. MR imaging (MRI) enables the measurement of the morphology/anatomy as well as the functional status of tissues under in vivo conditions. Compared to other in vivo imaging modalities, MRI has a high spatial resolution and allows for a remarkable soft tissue differentiation. MR spectroscopy (MRS) provides information on the biochemical/metabolic status of tissues. MR methods which have proven valuable in animal studies, can be readily translated to the clinical situation where MR-based diagnosis and treatment planning play a rapidly increasing role.After a short introduction into the principles of MR, we will illustrate the remarkable versatility of MR in research on brain injury from recent animal studies. Examples will be mainly drawn from experiments on early injury in focal cerebral ischemia and from research on mechanical brain trauma and excitotoxic lesions. The article ends with a brief description of the perspectives of MR in neuropsychiatry.

scholarly journals Influence of formic acid on the vitality of Strongyloides papillosus

2018 ◽  
Vol 9 (3) ◽  
pp. 435-439
Author(s):  
О. О. Boyko ◽  
O. G. Gavrilina ◽  
P. N. Gavrilin ◽  
Y. A. Gugosyan ◽  
V. V. Brygadyrenko
Keyword(s):  
Formic Acid ◽  
Laboratory Animals ◽  
Pest Species ◽  
Non Invasive ◽  
In Vivo Experiments ◽  
And Control ◽  
The Impact ◽  
Experimental Group

Formic acid (methanoic acid, HCOOH) is an organic compound which belongs to saturated monobasic acids. In natural conditions, it is secreted from the glands of ants, and also extracted from the leaves of stinging nettles. It is soluble in water in any proportions, which makes it practical to use for making aquatic solutions. It is broadly used as a preservative in the food industry – Е236 food additive (Codex Alimentarius), as a bactericide in medicine and veterinary medicine, and is also used against agricultural pest species of insects and mites. The in vitro and in vivo experiments revealed the anthelmintic properties of the acid against Strongyloides papillosus nematodes, parasites of the gastrointestinal tract of Ruminantia and rabbits. In the conditions of in vitro, 100% of (L1, L2, L3) nematode larvae died from a 1% solution of formic acid (10 g/l) after 24 hours exposure. When exposed to less strong concentrations of the acid (1, 0.1, 0.01, 0.001 g/l), vital forms of L3 S. papillosus were found. Non-invasive stages (L1, L2) are less resistant to the impact of the acid – death of 100% of the larvae was observed under the impact of 0.1% solution and up to 60% of larvae died at 0.01% solution of formic acid in the same conditions. LD50 for L3 invasive larvae of S. papillosus equaled 0.47%, and 0.0076% for L1, L2 non-invasive larvae of S. papillosus. In the conditions of in vivo experiment (with guinea pigs), the effective dose of formic acid was 0.4% ml/kg of the animal`s body weight. The results of the coproscopy after the treatment demonstrated absence of the helminth larvae in the feces of the laboratory animals during 10 days and their occurrence only on days 15–20 with a low intensity (90 larvae/g of feces on average). During an external examination of the corpses of the animals of the experimental group, no pathological changes were found. The intestine, the heart, the lungs and the liver of the animals from this group had no macroscopic changes – they were of natural colour and size. The hepatocytes looked normal and the structure of the liver lobes was maintained. In the tissues of the liver of the animals from the experimental and control groups, we found processes of passive congestion, and an insignificant degree of signs of hepatic steatosis.

scholarly journals Non-invasive diagnostics in fossils - Magnetic Resonance Imaging of pathological belemnites

2005 ◽  
Vol 2 (2) ◽  
pp. 133-140 ◽  
Author(s):  
D. Mietchen ◽  
H. Keupp ◽  
B. Manz ◽  
F. Volke
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Soft Tissue ◽  
Clinical Diagnostics ◽  
Resonance Imaging ◽  
Non Invasive ◽  
Physiological Processes ◽  
Magnetic Resonance Imaging Mri ◽  
Invasive Diagnostics

Abstract. For more than a decade, Magnetic Resonance Imaging (MRI) has been routinely employed in clinical diagnostics because it allows non-invasive studies of anatomical structures and physiological processes in vivo and to differentiate between healthy and pathological states, particularly of soft tissue. Here, we demonstrate that MRI can likewise be applied to fossilized biological samples and help in elucidating paleopathological and paleoecological questions: Five anomalous guards of Jurassic and Cretaceous belemnites are presented along with putative paleopathological diagnoses directly derived from 3D MR images with microscopic resolution. Syn vivo deformities of both the mineralized internal rostrum and the surrounding former soft tissue can be traced back in part to traumatic events of predator-prey-interactions, and partly to parasitism. Besides, evidence is presented that the frequently observed anomalous apical collar might be indicative of an inflammatory disease. These findings highlight the potential of Magnetic Resonance techniques for further paleontological applications.

scholarly journals BIMG-08. DEUTERIUM MAGNETIC RESONANCE SPECTROSCOPY USING 2H-PYRUVATE ALLOWS NON-INVASIVE IN VIVO IMAGING OF TERT EXPRESSION IN BRAIN TUMORS

2021 ◽  
Vol 3 (Supplement_1) ◽  
pp. i2-i2
Author(s):  
Georgios Batsios ◽  
Celine Taglang ◽  
Meryssa Tran ◽  
Anne Marie Gillespie ◽  
Joseph Costello ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
In Vivo Imaging ◽  
Lactate Production ◽  
Telomere Maintenance ◽  
Resonance Spectroscopy ◽  
Low Grade ◽  
Non Invasive ◽  
Tert Expression

Abstract Telomere shortening constitutes a natural barrier to uncontrolled proliferation and all tumors must find a mechanism of maintaining telomere length. Most human tumors, including high-grade primary glioblastomas (GBMs) and low-grade oligodendrogliomas (LGOGs) achieve telomere maintenance via reactivation of the expression of telomerase reverse transcriptase (TERT), which is silenced in normal somatic cells. TERT expression is, therefore, a driver of tumor proliferation and, due to this essential role, TERT is also a therapeutic target. However, non-invasive methods of imaging TERT are lacking. The goal of this study was to identify magnetic resonance spectroscopy (MRS)-detectable metabolic biomarkers of TERT expression that will enable non-invasive visualization of tumor burden in LGOGs and GBMs. First, we silenced TERT expression by RNA interference in patient-derived LGOG (SF10417, BT88) and GBM (GS2) models. Our results linked TERT silencing to significant reductions in steady-state levels of NADH in all models. NADH is essential for the conversion of pyruvate to lactate, suggesting that measuring pyruvate flux to lactate could be useful for imaging TERT status. Recently, deuterium (2H)-MRS has emerged as a novel, clinically translatable method of monitoring metabolic fluxes in vivo. However, to date, studies have solely examined 2H-glucose and the use of [U-2H]pyruvate for non-invasive 2H-MRS has not been tested. Following intravenous injection of a bolus of [U-2H]pyruvate, lactate production was higher in mice bearing orthotopic LGOG (BT88 and SF10417) and GBM (GS2) tumor xenografts relative to tumor-free mice, suggesting that [U-2H]pyruvate has the potential to monitor TERT expression in vivo. In summary, our study, for the first time, shows the feasibility and utility of [U-2H]pyruvate for in vivo imaging. Importantly, since 2H-MRS can be implemented on clinical scanners, our results provide a novel, non-invasive method of integrating information regarding a fundamental cancer hallmark, i.e. TERT, into glioma patient management.

scholarly journals Magnetic Resonance-Compatible Arm-Crank Ergometry: A New Platform Linking Whole-Body Calorimetry to Upper-Extremity Biomechanics and Arm Muscle Metabolism

2020 ◽  
Author(s):  
Riemer JK Vegter ◽  
Sebastiaan van den Brink ◽  
Leonora J Mouton ◽  
Anita Sibeijn-Kuiper ◽  
Lucas H.V. van der Woude ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Surface Electromyography ◽  
Motor Units ◽  
Daily Practice ◽  
Muscle Disease ◽  
Upper Body ◽  
Whole Body ◽  
Energetic Efficiency ◽  
The Impact

Abstract Background: Evaluation of the effect of human upper body training regimens may benefit from knowledge of local energy expenditure in arm muscles. To that end, we developed a novel asynchronous arm-crank ergometry platform for use in a clinical magnetic resonance (MR) scanner with 31P spectroscopy capability to study arm muscle energetics. The utility of the platform was tested in an investigation of the impact of daily practice on the energetic efficiency of execution of an arm-cranking task (ACT) in healthy subjects. Results: We recorded the first ever in vivo 31P MR spectra from the human biceps bracii muscle during ACT execution pre- and post-three weeks of daily practice bouts, respectively. Complementary datasets on whole body oxygen consumption, arm muscle electrical activity, arm-force and power output, respectively, were obtained in the mock-up scanner. The mean gross mechanical efficiency of execution of the ACT significantly increased 1.5-fold from 5.7 ± 1.2% to 8.6 ± 1.7% (P<0.05) after training, respectively. However, in only one subject this improvement was associated with recruitment of strictly oxidative motor units in the working biceps muscle. In all other subjects, biceps pH fell below 6.8 during exercise indicating recruitment of anaerobic motor units, the magnitude of which was either unaffected (two subjects) or even increased (two subjects) post-training. Surface electromyography and mechanical force recordings revealed that individuals employed various arm muscle recruitment strategies, using either predominantly elbow flexor muscles (two subjects), elbow extensor muscles (one subject,) or a combination of the two (two subjects), respectively. Three weeks of training improved muscle coordination but did not alter individual strategies. Conclusions: The new platform has produced the first ever in vivo dynamic data on human biceps energy and pH balance during upper body exercise. It allows evaluation of cyclic motor performance and outcomes of upper-body training regimens in healthy novices by integrating these new measurements with whole body calorimetry, surface electromyography and biomechanical measurements. This methodology may be equally valid for lower-limb impaired athletes, wheelchair users and patients with debilitating muscle disease.

Investigation of Stress Wave Propagation in Brain Tissues Through the Use of Finite Element Method

2010 ◽  
Author(s):  
Biaobiao Zhang ◽  
W. Steve Shepard ◽  
Candace L. Floyd
Keyword(s):  
Finite Element ◽  
Wave Propagation ◽  
Brain Injury ◽  
Stress Wave ◽  
Brain Research ◽  
Complex Structure ◽  
Stress Wave Propagation ◽  
Wave Loads ◽  
The Impact ◽  
The Brain

Because axons serve as the conduit for signal transmission within the brain, research related to axon damage during brain injury has received much attention in recent years. Although myelinated axons appear as a uniform white matter, the complex structure of axons has not been thoroughly considered in the study of fundamental structural injury mechanisms. Most axons are surrounded by an insulating sheath of myelin. Furthermore, hollow tube-like microtubules provide a form of structural support as well as a means for transport within the axon. In this work, the effects of microtubule and its surrounding protein mediums inside the axon structure are considered in order to obtain a better understanding of wave propagation within the axon in an attempt to make progress in this area of brain injury modeling. By examining axial wave propagation using a simplified finite element model to represent microtubule and its surrounding proteins assembly, the impact caused by stress wave loads within the brain axon structure can be better understood. Through conducting a transient analysis as the wave propagates, some important characteristics relative to brain tissue injuries are studied.

scholarly journals Brain Injury and Recovery Following Binge Ethanol: Evidence from In Vivo Magnetic Resonance Spectroscopy

2010 ◽  
Vol 67 (9) ◽  
pp. 846-854 ◽  
Author(s):  
Natalie M. Zahr ◽  
Dirk Mayer ◽  
Torsten Rohlfing ◽  
Michael P. Hasak ◽  
Oliver Hsu ◽  
...  
Keyword(s):  
Brain Injury ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Resonance Spectroscopy ◽  
Binge Ethanol

Quality of design and reporting of animal research in peritoneal dialysis: A scoping review

2020 ◽  
Vol 40 (4) ◽  
pp. 394-404
Author(s):  
Janusz Witowski ◽  
Dorota Sikorska ◽  
András Rudolf ◽  
Izabela Miechowicz ◽  
Julian Kamhieh-Milz ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Scoping Review ◽  
Animal Studies ◽  
Reporting Quality ◽  
Animal Research ◽  
Size Estimation ◽  
Quality Of Reporting ◽  
The Impact

The concerns about reproducibility and validity of animal studies are partly related to poor experimental design and reporting. Here, we undertook a scoping review of the literature to determine the extent and quality of reporting of animal studies on peritoneal dialysis (PD). Online databases were searched to identify 567 relevant original articles published between 1979 and 2018. These were analyzed with respect to bibliographic parameters and general aspects of animal experimentation. A subgroup of 120 studies was analyzed in detail in terms of the impact on the reporting quality of the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines for animal studies. The number of animal studies on PD increased continuously over the years with a thematic shift toward long-term preservation of the peritoneum as a dialyzing organ. There were significant deficiencies in research design with the lack of sample size estimation, randomization, and blinding being the commonest shortcomings. The description of animal numbers, housing conditions, use of medication, and statistical analysis was incomplete. The introduction in 2010 of the ARRIVE guidelines produced very little improvement in the completeness of reporting regardless of journal impact factor. The animal studies on PD suffer from deficits in experimental protocols and transparent reporting. These drawbacks need to be corrected to ensure high-quality and much-needed animal research in PD.

scholarly journals The Rapid Decrease in Astrocyte-Associated Dystroglycan Expression by Focal Cerebral Ischemia is Protease-Dependent

2007 ◽  
Vol 28 (4) ◽  
pp. 812-823 ◽  
Author(s):  
Richard Milner ◽  
Stephanie Hung ◽  
Xiaoyun Wang ◽  
Maria Spatz ◽  
Gregory J del Zoppo
Keyword(s):  
Cerebral Ischemia ◽  
Basal Lamina ◽  
Focal Cerebral Ischemia ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Receptor Expression ◽  
Cerebral Microvessels ◽  
The Impact

During focal cerebral ischemia, the detachment of astrocytes from the microvascular basal lamina is not completely explained by known integrin receptor expression changes. Here, the impact of experimental ischemia (oxygen—glucose deprivation (OGD)) on dystroglycan expression by murine endothelial cells and astrocytes grown on vascular matrix laminin, perlecan, or collagen and the impact of middle cerebral artery occlusion on αβ-dystroglycan within cerebral microvessels of the nonhuman primate were examined. Dystroglycan was expressed on all cerebral microvessels in cortical gray and white matter, and the striatum. Astrocyte adhesion to basal lamina proteins was managed in part by α-dystroglycan, while ischemia significantly reduced expression of dystroglycan both in vivo and in vitro. Furthermore, dystroglycan and integrin α6β4 expressions on astrocyte end-feet decreased in parallel both in vivo and in vitro. The rapid loss of astrocyte dystroglycan during OGD appears protease-dependent, involving an matrix metalloproteinase-like activity. This may explain the rapid detachment of astrocytes from the microvascular basal lamina during ischemic injury, which could contribute to significant changes in microvascular integrity.

scholarly journals Introduction to in vivo31P magnetic resonance spectroscopy of (human) skeletal muscle

1999 ◽  
Vol 58 (4) ◽  
pp. 861-870 ◽  
Author(s):  
A. Heerschap ◽  
C. Houtman ◽  
H. J. A. in 't Zandt ◽  
A. J. van den Bergh ◽  
B. Wieringa
Keyword(s):  
Skeletal Muscle ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Current Status ◽  
Resonance Spectroscopy ◽  
Biochemical Processes ◽  
Non Invasive ◽  
Introductory Overview ◽  
Muscle Biochemistry

31P magnetic resonance spectroscopy (MRS) offers a unique non-invasive window on energy metabolism in skeletal muscle, with possibilities for longitudinal studies and of obtaining important bioenergetic data continuously and with sufficient time resolution during muscle exercise. The present paper provides an introductory overview of the current status of in vivo31P MRS of skeletal muscle, focusing on human applications, but with some illustrative examples from studies on transgenic mice. Topics which are described in the present paper are the information content of the 31P magnetic resonance spectrum of skeletal muscle, some practical issues in the performance of this MRS methodology, related muscle biochemistry and the validity of interpreting results in terms of biochemical processes, the possibility of investigating reaction kinetics in vivo and some indications for fibre-type heterogeneity as seen in spectra obtained during exercise.

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